EU's Tusk says some UK reform demands 'unacceptable'

EU president Donald Tusk warned that some of the reform demands British Prime Minister David Cameron is due to make at a summit Thursday are likely to be unacceptable to other leaders.

"The consultations I have led with all member states show the goodwill of the participants but it doesn't change the fact that some parts of the British proposal seem unacceptable," he told reporters.

"However, if prime minister Cameron persuades leaders tonight that we can work together to find solutions regarding all four baskets, we will have a real chance to strike a deal in February."

During a summit dinner on Thursday evening, Cameron will lay out his demands for reforms in European Union in four areas or "baskets" ahead of a British referendum to be held by the end of 2017.

The most controversial is a demand for a four-year limit before EU migrants working in Britain can claim benefits such as social housing or child welfare payments, which other leaders feel is discriminatory.

Tusk and Cameron have said they are aiming for a final deal at the next scheduled EU summit in two months.